Characteristics of Streamer Discharge Along the Insulation Surface With Embedded Electrode

Abstract

Surface discharge was a common accident in power systems, significantly impacting the safe and stable operation of the power grid. The insulation structure of power equipment was intricate, and surface discharge characteristics were influenced not only by the insulation material but also by electrode geometry. In the paper, characteristics of streamer discharge along the insulation surface with embedded electrode were investigated under negative DC voltage. The streamer propagation field, velocity, and luminous intensity, were measured by photomultiplier tubes and ICCD camera. Unexpectedly, the disparity in the characteristics of streamer discharge along the insulation surface, with and without an embedded electrode, was substantial. Furthermore, the investigation also revealed that the length of the embedded electrode has a significant influence on the characteristics of surface streamer discharge. Through analysis, it had been determined that the presence of the embedded electrode did not significantly impact the electric field along the insulation surface. However, it had an influence on the charge distribution on the insulation surface, consequently affecting the characteristics of surface steamer discharge. The findings from this research would provide valuable technical support for enhancing external insulation design and operation strategies in DC bushings and other related equipment.